OBJECTIVES To quantify the variability in lifting motions, trunk moments, and spinal loads associated with repeated lifting exertions and to identify workplace factors that influence the biomechanical variability. DESIGN Measurement of trunk dynamics, moments and muscle activities were used as inputs into EMG assisted model of spinal loading. BACKGROUND Traditional biomechanical models assu...

Neurophysiological studies are often designed to examine relationships between measures from different testing conditions, time points, or analysis techniques within the same group of participants. Appropriate statistical techniques that can take into account repeated measures and multivariate predictor variables are integral and essential to successful data analysis and interpretation. This wo...

OBJECTIVES To introduce multilevel repeated measures (RM) models and compare them with multilevel difference-in-differences (DID) models in assessing the linear relationship between the length of the policy intervention period and healthcare outcomes (dose-response effect) for data from a stepped-wedge design with a hierarchical structure. DESIGN The implementation of national essential medic...

The purposes of this study were to establish the reliability for measuring scapular muscle thickness, and to examine how scapular muscle thickness changes with respect to external loads. Participants were asymptomatic subjects recruited from a sample of convenience. Thickness Measures were taken using rehabilitative ultrasound imaging (RUSI) under 11 conditions, rest and 10 progressive loads, f...

We assessed upper airway responses to acute and chronic inspiratory loading. In Experiment I, 11 healthy subjects underwent T(2)-weighted magnetic resonance imaging (MRI) of upper airway dilator muscles (genioglossus and geniohyoid) before and up to 10 min after a single bout of pressure threshold inspiratory muscle training (IMT) at 60% maximal inspiratory mouth pressure (MIP). T(2) values for...